Metabolic fingerprinting of gilthead seabream (Sparus aurata) liver to track interactions between dietary factors and seasonal temperature variations.

Tomé S Silva,Luís E.C Conceição,Ana M.R Da Costa,Nadège Richard,Pedro M.L Rodrigues,Jorge P Dias

doi:10.7717/peerj.527

Tomé S Silva, Luís E.C Conceição + Show 4 more

Open Access

https://doi.org/10.7717/peerj.527

Copy DOI

Journal: PeerJ	Publication Date: Aug 26, 2014
Citations: 46	License type: cc-by

Affiliation: University of Algarve, Sparos (Portugal)

Abstract

Farmed gilthead seabream is sometimes affected by a metabolic syndrome, known as the “winter disease”, which has a significant economic impact in the Mediterranean region. It is caused, among other factors, by the thermal variations that occur during colder months and there are signs that an improved nutritional status can mitigate the effects of this thermal stress. For this reason, a trial was undertaken where we assessed the effect of two different diets on gilthead seabream physiology and nutritional state, through metabolic fingerprinting of hepatic tissue. For this trial, four groups of 25 adult gilthead seabream were reared for 8 months, being fed either with a control diet (CTRL, low-cost commercial formulation) or with a diet called “Winter Feed” (WF, high-cost improved formulation). Fish were sampled at two time-points (at the end of winter and at the end of spring), with liver tissue being taken for FT-IR spectroscopy. Results have shown that seasonal temperature variations constitute a metabolic challenge for gilthead seabream, with hepatic carbohydrate stores being consumed over the course of the inter-sampling period. Regarding the WF diet, results point towards a positive effect in terms of performance and improved nutritional status. This diet seems to have a mitigating effect on the deleterious impact of thermal shifts, confirming the hypothesis that nutritional factors can affect the capacity of gilthead seabream to cope with seasonal thermal variations and possibly contribute to prevent the onset of “winter disease”.

Highlights

Metabolomics is usually defined as the holistic study of metabolites in living systems, which includes most molecules present apart from polynucleotides (mostly studied byHow to cite this article Silva et al (2014), Metabolic fingerprinting of gilthead seabream (Sparus aurata) liver to track interactions between dietary factors and seasonal temperature variations
The second approach, metabolic fingerprinting, avoids altogether the deconvolution of the mixture into its different components and attempts to capture a multivariate fingerprint of a biological sample in some arbitrary feature space in a way that the similarity of samples in the “real” metabolomic feature space can be deduced/estimated from their similarity in the fingerprinting space. Techniques such as 1H-NMR, 13C-NMR, DIMS (Direct Injection Mass Spectrometry), vibrational (FT-IR or Raman) spectroscopy and pyrolysis mass spectrometry have been commonly used, which, not nearly as sensitive and specific as hyphenated methods, are often less expensive, quicker and/or require less sample preparation (Dettmer, Aronov & Hammock, 2007; Dunn & Ellis, 2005; Ellis et al, 2007). This manuscript describes the results of a trial in which we explored the use of transmissive FT-IR spectroscopy for metabolic fingerprinting of liver tissue from gilthead seabream (Sparus aurata), to better understand how seasonal temperature variations and dietary factors affect the hepatic metabolic content
The results indicate that season had a strong negative impact on the hepatic glycogen reserves of gilthead seabream and that the dietary treatment generally had the opposite effect: are carbohydrate stores higher in winter feed (WF)-fed fish compared to control feed (CTRL)-fed, at the end of winter, but this increase is still visible at the end of spring, despite observed depletion of carbohydrate stores between the two sampling points, for both diets

Summary

Introduction

Metabolomics is usually defined as the holistic study of metabolites in living systems, which includes most molecules present apart from polynucleotides (mostly studied byHow to cite this article Silva et al (2014), Metabolic fingerprinting of gilthead seabream (Sparus aurata) liver to track interactions between dietary factors and seasonal temperature variations. The second approach, metabolic fingerprinting, avoids altogether the deconvolution of the mixture into its different components and attempts to capture a multivariate fingerprint of a biological sample in some arbitrary feature space in a way that the similarity of samples in the “real” metabolomic feature space can be deduced/estimated from their similarity in the fingerprinting space For this purpose, techniques such as 1H-NMR, 13C-NMR, DIMS (Direct Injection Mass Spectrometry), vibrational (FT-IR or Raman) spectroscopy and pyrolysis mass spectrometry have been commonly used, which, not nearly as sensitive and specific as hyphenated methods, are often less expensive, quicker and/or require less sample preparation (Dettmer, Aronov & Hammock, 2007; Dunn & Ellis, 2005; Ellis et al, 2007)

Methods

Results

Conclusion